Lets analyse this situation as it is very practical one and everyday people will face it.
GST is applicable on supply of goods or service or both. In this case Rs. 60 you received is against bank charges. You have not provided any goods or service. So, prima facie GST should not be charged.
However looking at the valuation rules, GST should be paid on reimbursements. In your case 60 Rs. was part of cost of supply which you recovered from customer and GST should be charged.
In my opinion, you have to charge GST on Rs. 60 and issue an invoice for 60 Rs. with GST included.